NIR application on Skeleton muscle oxygenation
Ongoing (May 2017_Present)
Application of Near Infrared Spectroscopy (NIRs) for measurement of hemodynamic of skeleton muscle and assessment of muscle metabolism under rest condition and after dynamic exercise.
Source of Support:
Iran Football Medical Assessment and Rehabilitation Centre (IFMARC), Tehran, Iran
Project Summary
This proposal is outlined for application of near infrared spectroscopy (NIRs) for measurement of hemodynamics of skeleton muscle and measurement of tissue oxygenation. Supply of sufficient oxygen to muscle tissues through blood flow and its oxygenated hemoglobin content is essential for oxidative metabolism and healthy function of muscle tissues. While the project in its broad context is designed for the use of NIRs in sport medicine tuned for assessment of muscle physiological conditions, in this project we will deal with evaluation of effectiveness of NIRs for identifying changes in muscle physiological condition. Physiological condition will be assessed by measurement of pattern of muscle oxygenation under predesigned exercise condition as compared with rest condition.
This project outline consists of the following sections
In section 1 project primary and secondary objectives are outlined. In this section primary queries that this project tuned to respond to are also given. In section 2 introductory remarks are given on muscle tissue oxygenation and oxidative metabolism with reference to gold standard measurement system with advantages of NIRs as compared with such system. In section 3, brief reference is made on NIR technology and principle of NIR spectroscopy. Section 4 will deal with project implementation details ( to be detailed).
Objectives
Primary Objective:
- Investigation as to feasibility of application of near infrared spectroscopy (NIRs) for measurement of skeleton muscle tissue oxygenation as a measure of muscle metabolism under set of predefined test conditions. Two conditions are considered: rest and after a set of predefined exercise conditions. It is assumed that a set of carefully selected test protocols including subject selection, number and duration of tests will be specified.
- Accuracy of NIR application in selected application consisting of measurement of skeleton muscle oxygenation during predefined rest and exercise condition as compared with data gathered from treadmill test results reported in literature or measured with other means such as phosphorous MRI.
Secondary Objectives:
- Evaluation of stability of NIR data for assessment of accuracy of results using intra and intra variability of tissue oxygenation data.
- Evaluation of applicability of NIRs in other application areas that hemodynamics of human tissue play an important role for proper functionality and performance of these tissues including skeleton muscle and other tissues. Such information can be of significance for assessment of sport training program and planned exercise activities. We note there are several areas in sport medicine ( other than skeleton muscle) that such questions are raised.
Principle assumptions:
A high metabolism in a muscle is an indicative of muscle high activity and performance during exercise and sport activity. Metabolism is measured mainly by oxygen supply ( measured by Oxy hemoglobin) and rate of oxygen consumption ( measured with deoxyy hemoglobin concentration ). Alternatively blood flow are also used.
Secondary assumptions:
We assume data are gathered under carefully designed test conditions and protocol. This includes sufficiently stable test conditions and are collected for a sufficient time period from which suitable representative sections belonging to rest and exercise conditions could be selected. Test protocols will be carefully designed. It is assumed that other vital signs will also be measured during tests detail of which will be given in test plans.
Some of the queries that this project is to answer:
- What significant differences in the NIR data belonging to the two conditions. Differences can be measured by statistics of data or features extracted from the data. Draft Are these differences significant to accept NIR as a reliable method for tissue oxygenation measurement.
- What are the complexity of using NIRs in preselected selected area including skeleton muscle performance evaluation
- What are inter and intra variability of NIRs data selected data belonging to two groups of data i.re. rest and exercise conditions. We assume data re gathered for a sufficient time period and for sufficient number of subjects from which suitable representative sections belonging to rest and exercise conditions could be selected.
Section 2. Introductory Remarks on muscle tissue oxygenation
Supply of sufficient oxygen to muscle tissues through blood flow and oxygenated hemoglobin is essential for oxidative metabolism and healthy function of muscle tissues. There has been considerable interest on the subject by various research groups during past twenty years. These research have been concerned with identifying means by which such measurement can be made unintrusively . Among these methods, phosphorus magnetic resonance spectroscopy (PMRS) is considered to be “a gold standard”. PMRS was first applied for the measurement of human skeletal muscle metabolism [Cresshull et al 1981 (9)]. Phosphate metabolites is considered to play an important role in muscle metabolism, especially in oxidative phosphorylation during exercise (2) and recovery (1). With introduction of NIR spectroscopy, several research groups have applied NIRs on measurement of human muscle oxygenation. Application of near-infrared spectroscopy was first reported in 1985 It was applied to the study of skeletal muscle in humans during exercise. Considerable studies have been done sine 1985).
Section 3 Brief remarks on the theory and principle of NIR spectroscopy as applied for measurement of muscle oxidation
NIR spectroscopy is based on applying light photons at the near infrared wavelength ( 600-1000nm) on the tissue which is then partially diffused, absorbed and partially reflected back to the surface to be measured by the receiving probes. Two main chromospheres as absorbents of light photons are oxy and deoxy-hemogloin and with partial absorption by myoglobin. Measurement of oxy/deoxy hemoglobin concentration requires knowledge of absorption coefficient of the media (muscle tissue)as well as path length. A common approach is to use two wavelength for the NIR incident light and where measured values are then used to evaluate oxy/deoxy concentration using Beer Lambert law. For generating incident light ,a common strategy is to use continuous wave strategy to apply NIR photons on the tissue Under continuous wave light transmission relative changes of hemoglobin concentration from reference base line ( in contrast to absolute values) are measured. However they can be used to determine the balance between O2 supply and O2 consumption where the knowledge of O2supply is utilized to estimate muscle O2 consumption. Other approaches have also been used to estimate muscle O2 consumption quantitatively. This is done by multiplying the muscle O2 consumption ratio by the muscle resting metabolic rate measured using phosphorus magnetic resonance spectroscopy.
Project implementation plan and project phases( to be detaild)
Outlining derails of the test plan including
- identification of skeleton muscle for tests Test will be all in stand still condition
- subject selection, age groups, other specs
- Test protocol including test duration
- other conditions
- Selected references relevant to proposed project
- Discussion with DR Kord of sport medicine research center (of University of Tehran) on the project
- Exploring funding sources and filling out project application form for
Collaborator:
Dr.Mansoor Fatehi
Director, Medical Imaging Informatics Research Center at Tehran
Chairman of the Board, Sorenahealth, Iranian Modern Health Strategies
Adjunct Professor of Electrical and Computer Engineering at The University of British Columbia
Head of Iran Football Medical assessment and Rehabilitation Centre (IFMARC)
FIFA Medical Officer
AFC Medical Committee member
Medical Director of Iranian Football League Organization
Iranian association of sports and exercise medicine member
